One of the most discussed concepts about authentication today is the concept of Single Sign-On, or SSO. SSO is the ability for a user to log into one location, and authenticate across several domains without entering any additional credentials. This saves the user from having to enter several credentials for related websites, as well as possibly prevent the user from having to remember multiple logins.

While developing the Rolling Stone and Vogue Archives, we needed a SSO system that could integrate our ASP.Net based archive with each provider’s existing authentication systems, primarily Apache-based web applications. Our solution was to develop a C# implementation of mod_auth_tkt cookie-and-token based authentication system, which we have since released open source.